A genome-wide association study for recurrent laryngeal neuropathy in the Thoroughbred horse identifies a candidate gene that regulates myelin structure.

Authors: McGivney Charlotte L, McGivney Beatrice A, Farries Gabriella, Gough Katie F, Han Haige, Holtby Amy R, MacHugh David E, Katz Lisa Michelle, Hill Emmeline W

Journal: Equine veterinary journal

DOI: 10.1111/evj.14461 PubMed: 39791379Log in to save

Summary

Recurrent laryngeal neuropathy remains one of the most costly upper respiratory conditions in Thoroughbreds, yet despite evidence of heritability, previous genetic studies have been confounded by the breed's strong selection for height. McGivney and colleagues conducted a genome-wide association study in Thoroughbreds using rigorous clinical phenotyping protocols to identify genetic variants associated with RLN independent of body size. They identified a candidate gene regulating myelin structure—the insulating layer around nerve fibres—suggesting that compromised neural insulation rather than simply nerve compression contributes to disease development. This discovery shifts our understanding away from the long-held assumption that RLN is purely mechanical (related to height and recurrent laryngeal nerve length), opening new avenues for both diagnostic screening and potential therapeutic intervention targeting nerve integrity. For practitioners involved in breeding decisions, veterinary management, or investigating performance-limiting respiratory disease, these findings provide a molecular foundation for recognising RLN as a primary nerve pathology rather than an inevitable consequence of size.

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Practical Takeaways

•Genetic screening may become possible for RLN risk in Thoroughbreds, enabling breeding decisions to reduce disease incidence in performance horses
•Standardized clinical assessment protocols for RLN are essential for accurate diagnosis and genetic research applications
•Understanding the genetic basis of RLN opens new avenues for potential therapeutic interventions targeting myelin integrity and neurological function

Key Findings

•Genome-wide association study identified candidate genes regulating myelin structure associated with RLN risk in Thoroughbreds independent of height
•Clinical assessment methodology is critical for accurate RLN phenotyping in genetic studies
•RLN has a significant genetic contribution to disease risk in Thoroughbred horses

Conditions Studied

recurrent laryngeal neuropathy (rln)upper respiratory tract disease

Related References

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